Injectable parenteral drugs are typically packaged in parenteral vials. Packing of such parenteral drugs may include processing steps that are specific to such parenteral vials and the drugs packaged therein. Such injectable parenteral drugs may be provided to the consumer in liquid or freeze dried form. For freeze dried parenteral drugs, the vial containing the drug is closed with a lyophilization stopper, and undergoes a lyophilization step, prior to closing of the vial. The vials are then closed by standard stoppers, and a metal crimp is applied around the vial rim to retain the stopper therein. Vials containing liquid parenteral drugs are provided with a stopper that sealingly engages the vial at the filling point. Vial filling and packaging can take place via a filling line, with the vials housed in a vial tray such as that disclosed in U.S. Provisional Patent Application No. 61/767,496, which is incorporated herein by reference as if fully set forth. During application of the metal crimp, vials are typically lifted out from the tray, so that the crimp applying apparatus can adequately access the vial rim. Furthermore, in the case of freeze dried drugs, the additional step of lyophilization requires the ability of vaporized moisture removed from the parenteral drug to exit during processing. This step typically takes place outside of the tray. A need exists for a mechanism that functions similarly to the metal crimp used to close parenteral vials, while allowing escape of vapors during lyophilization. A further need exists for such a mechanism that can be applied without lifting the vial out of the processing tray, in order to simplify processing. A further need exist to standardize the stopper and cap, eliminating the need for specific caps for liquid and dried parenteral drugs. Such a mechanism would advantageously allow for simplified processing of liquid and dried parenteral drugs together.